A memristor is a name given to any sort of two-terminal circuit elements that are both passive and sustain the important relationship between voltage and current and the time integrals of both. In other words, a memristor is used because of a phenomenon known as memristance. To understand what a memristor is, one must first appreciate what memristance is. This leads to the question: What is Memristance? Memristance is, as the name suggests, the memory resistance. If a charge flows in one direction, the resistance found within that circuit is Read More

XM Radio is a type of satellite radio that is extremely popular with people that want more entertainment and programming choices from their radio with less commercials and interruptions. XM Radio is similar to cable TV as users pay a small fee each month to receive superior programming. In XM Radio’s case, users can receive over 150 different channels, many with commercial free music, talk show personalities, and quality sports programming such as Major League Baseball and NASCAR. In order to receive XM Radio, users must first have a special Read More

It is the standard form of electricity distribution from the power station to the powerpole. Three wires carry three currents that are identical except for their cycles being shifted one third of a cycle from each other. Electrical systems that use more than one phase are called polyphase systems. Power Station Power stations usually have one generator for each phase. For each bank of generators, three wires carry the current to the grid, along with a neutral wire which is earthed at the station. Electrical towers carry the three lines Read More

A resistor restricts the flow of current. It is a basic component of all electrical devices, even the filament in a light globe is a resistor. Resistors are defined by their material type, resistance, power rating, and tolerance. Resistor Types There are four main types of resistor: carbon, film, wirewound, and semiconductor. Carbon resistors are tiny insulated cylinders of carbon and ceramic dust with a terminal at each end. They have colored bands to show their resistance and tolerance values. Film resistors are similar to carbon resistors, but use a Read More

MCPC stands for Multiple Channel Per Carrier. MCPC is a form of satellite transmission where each carrier is utilized to transmit multiple channels. MCPC transmits multiple video or audio channels on one carrier by utilizing Time Division Multiplexing (TDM). The alternative to MCPC is SCPC (Single Channel Per Carrier). MCPC is used much more than SCPC because it makes much more efficient use of expensive satellite bandwidth.

The transistor is a solid-state component that uses a small current to control the flow of a large current. It is used mainly in amplification, detection, and switching. The transistor is one of the most important inventions of modern times. They are smaller, cheaper, and use less power than the vacuum tubes they replaced. Without transistors, the modern computer age would not be possible. History of the Transistor The transistor was invented in 1947 by three Americans at Bell Laboratories: John Bardeen, Walter Brattain, and William Shockley. They were trying Read More

A thermostat is a device that allows users to input a specific temperature into an air conditioner. Thermostats are often included in virtually every type of air conditioner including home air conditioning units, industrial air conditioners, and automotive air conditioners. Thermostats can also be used in cooling or heating units where an extreme temperature must be maintained at all times. Thermostats are relatively simple in design and are generally highly user-friendly. Mercury Switch A mercury switch consists of a glass vial of mercury connected to three separate wires and is Read More

VSWR (Voltage Standing Wave Ratio) is a metric commonly used with antenna systems for ham or shortwave radio communication. VSWR is normally defined as a ratio with a 1:1 VSWR, indicating that there is an exact or perfect match between all antenna system elements. The VSWR can also be expressed by comparing Vmax with Vmin in a ratio. Why does VSWR Exist? In order to obtain maximum power from a load, the load and generator impedance must match. If there is any mismatch or difference, then maximum power transfer does Read More

The SMA (SubMiniature Type A) connector is a type of the radio frequency connector developed in the 1960s to make it easier to connect coaxial cables. Using a screw-type design instead of the common ‘push-pull’ system, the SMA connector allows for a quick connection; and can be used in both alternating and direct current applications. Just like BNC connectors, SMA connectors find use in video and Ethernet applications. The SMA connector can be of two types, the 905 and the 906. The 905 type has a straight connector, while the Read More

A spark-gap transmitter is a mechanism for producing radio signals. It has been the primary radio transmission device during the early years of radio technology. It was soon superseded by other transmitters due to its discontinuous radio wave production and widely varying frequencies. How a Spark-Grap Transmitter Works A spark gap transmitter is basically composed of two capacitors (electrical apparatus designed to store electrical energy). However, the switch that ultimately forms the connection between the two capacitors is ionized gas (the air gap) that facilitates the passage of an oscillating Read More